i personally bought a nokia 6500c a couple months ago, and bought it for same reasons - bluetooth with n800 to get internet, and small. it's slightly tall but very thin so i like it, and is high-speed internet which claims to be one of the fastest. works perfectly for what i want, very pleased.

i'm not sure how long normal phones last but it lasts a bit over 2 days i would say (with pretty regular use mind)